ATHENS — For 2,500 years, the six sisters stood unflinching atop the Acropolis, as the fires of war blazed around them, bullets nicked their robes, and bombs scarred their curvaceous bodies. When one of them was kidnapped in the 19th century, legend had it that the other five could be heard weeping in the night.

But only recently have the famed Caryatid statues, among the great divas of ancient Greece, had a chance to reveal their full glory.

For three and a half years, conservators at the Acropolis Museum have been cleaning the maidens, Ionic columns in female form believed to have been sculpted by Alkamenes, a student of ancient Greece’s greatest artist, Phidias. Their initial function was to prop up a part of the Erechtheion, the sacred temple near the Parthenon that paid homage to the first kings of Athens and the Greek gods Athena and Poseidon.

Today they are star attractions in the museum; the originals outside were replaced with reproductions in 1979 to keep the real maidens safe.

Over the centuries, a coat of black grime came to mask their beauty. Now conservators have restored them to their original ivory glow, using a specially developed laser technology.

To coincide with the museum’s fifth anniversary, the women — minus one — went on full display in June, gleaming from their modern makeover. The missing Caryatid is installed at the British Museum in London, which acquired it nearly two centuries ago after Lord Elgin, the British ambassador to the Ottoman Empire, had it sawed off the Erechtheion’s porch, along with shiploads of adornments from the Parthenon to decorate his mansion in Scotland before selling the pieces to pay debts.

Greek and British authorities have long fought over the return of these so-called Elgin marbles, a dispute that heated up again recently when the actors George Clooney, Matt Damon and Bill Murray came out in support of the sculptures’ being returned home during an appearance in London for the movie “The Monuments Men.” That ignited a firestorm in Britain, which maintains that Lord Elgin saved the marbles from destruction, and acquired them fairly.

“Someone needs to restore George Clooney’s marbles,” London’s mayor, Boris Johnson, retorted. The controversy may flare anew as the British Museum plans an exhibit of the human body in Greek sculpture for next spring, using some of the marbles from the Parthenon.

Greeks have not been shy about using the Caryatid restoration to help press their case. While the Caryatids’ restoration is not part of a specific campaign to get the marbles back, the fresh cleaning shows that the museum can support their return, said Dimitris Pantermalis, the president of the Acropolis Museum.

“We insist on a solution” to the Elgin marbles, Mr. Pantermalis said. “A country must be ready when it claims something, and the Acropolis Museum has completed this.”

In the meantime, the missing Caryatid is glaring in its absence from the platform, a subversive display of resistance that is reflected one floor up in the museum, where large swaths of the Acropolis frieze owned by the British Museum are represented as chalky plaster copies of the originals. On a recent weekday, Mr. Pantermalis wove through crowds who stood enthralled around a special dais on which the five remaining Caryatids were displayed. “With the pollution erased, we can read more about the history of the last 2,500 years,” he said.

Knots of people were glued to a video screen showing footage of the cleaning project, which was set up on the floor of the museum. Conservators wearing dark goggles wielded a dual-wavelength laser developed by the Foundation for Research and Technology-Hellas in Crete, a system that was also employed to restore the Parthenon’s west frieze and the high-relief metopes that adorned the east entrance. Beams of infrared and ultraviolet radiation pulsed across the hem of one Caryatid’s robes, burning soot millimeter by millimeter to reveal the apricot-tinted patina of the original marble.

Starting in 2011, a team of six Greek conservators focused on one Caryatid at a time, setting up fabric rooms around each statue and mapping its surface before attacking an ebony mantle of pollution that had thickened when Athens became a modern metropolis filled with car exhaust, factory fumes and acid rain. Along the way, the conservators found traces of an enormous fire set in the first century B.C. by the Roman general Sulla, and chunks of marble from clumsy repair jobs attempted centuries ago.

It took six to eight months to transform each statue from night into day, with the crews rotating shifts to avoid fatigue. The in-house restoration costs were minimal and funded with income from ticket and museum shop sales, said Costas Vassiliadis, a conservator who heads the restoration team.

“It looked almost like tattoo removal,” said Shawn Hocker, a tourist who had traveled to the Acropolis with his wife and friends from Wilmington, N.C. “You can imagine what they looked like in the ancient world.”

The museum plans to clean a number of other architectural sculptures from the Acropolis, using the laser technology, Mr. Vassiliadis said, although he declined to give details because the new projects had not yet been announced.

In their original setting, the Caryatids stood on the porch of the Erechtheion, with a sweeping southern view toward the Aegean Sea. They rested in contrapposto poses, three of them standing firmly on their right legs, demurely bending their left knees beneath diaphanous robes. The others stood in opposite pose. Together they held up a part of the temple’s massive roof.

The Caryatids’ origins were less poetic: According to one legend, Mr. Pantermalis said, the statuesque maidens were not intended to be glorified, but condemned to stand in penance at the temple for eternity to atone for an ancient treachery committed by their hometown, Caryae, a Greek city near Sparta that took the side of the Persians against the Greeks during the Greco-Persian Wars. Other historians say young women from the city who danced for the goddess Artemis were inspirations. The statues remained nameless, and even today they go simply by the letters A, B, C, D, E and F, Mr. Vassiliadis said.

Under the Ottoman Empire, the Erechtheion was converted into a harem, an indignity that the Caryatids survived. Soon after, in 1687, they were nicked by bullets and debris when the Parthenon was shelled during a battle between the Turks and the Venetians.

But officials say the modern equivalent of that destruction is the gaping hole that was left when Lord Elgin made off with the statue.

Mr. Pantermalis glanced out the window toward the Parthenon, leaning into the sky from the soaring rock of the Acropolis. “It’s been 200 years,” he said, returning his gaze to the Caryatids. “We think in the framework of the new museum, it’s possible to reunite our treasures.”

Correction:

An article on Tuesday about the restoration of the Caryatid statues that have recently gone back on display at the Acropolis Museum misidentified the conflict in which the city of Caryae, from which the statues’ name is derived, sided with the Persians against the Greeks. It was during the Greco-Persian Wars, not the Peloponnesian War, in which Greeks fought one another. The article also misstated the time period since the British Museum acquired one of the Caryatids. It was nearly two centuries ago, not one.